[DonC]

ERA uses a center windshield bracket and you might be able to get one from them.
Whatever you go with pay heed to the horror stories about windshield frame screws cracking the windshield. Make absolutely sure the screws in the frame don't contact the glass when the windshield is in the frame. A careful fitting of the bracket to the frame should do it.
The ERA cowl is heavy enough to use sheet metal screws. If you order the bracket from ERA ask Bob what size they use when you order it.
Pre fit the windshield frame without the glass in it but the bracket attached. Check that the bend angle of the bracket is correct and adjust if necessary. Mark, drill and screw the bracket to the body. That way you won't have to be letting the screws create the threads in the fiberglass at the final assembly. On final assembly you can turn the crews counterclockwise and feel them align with the preformed threads. With the glass in the frame you'll have very little room to work. Harbor Freight makes a neat little 1/4 drive ratchet with a set of 4 bits that should get the final mounting done with a minimum of fuss.
DonC